The proposed bill aims to incentivize the adoption of grid-connected residential battery energy storage systems in Washington State. It establishes a framework for qualified light and power businesses to create battery incentive programs, which must be approved by the Washington State University extension energy program. The bill outlines definitions for key terms, such as "residential battery energy storage system" and "qualified light and power business customer," and mandates that at least 40% of the benefits from these programs must support low-income and moderate-income households. The incentive payments for customers will range from $450 to $765 per kilowatt-hour of battery storage capacity, depending on income levels, and the program will be available from July 1, 2026, to June 30, 2036.

Additionally, the bill provides tax credits for light and power businesses that participate in the incentive program, covering the costs of incentive payments and related expenses. It includes provisions for performance evaluation, requiring the joint legislative audit and review committee to assess the effectiveness of the tax preference by 2030, with specific goals for battery energy storage installation and job growth in the clean energy sector. The bill also emphasizes the importance of data collection to monitor the program's success and compliance, ensuring transparency and accountability in the implementation of these incentives.